The present invention generally relates to apparatus for controlling various apparatus and is more particularly directed to a foot operated control for ophthalmic surgical apparatus such as, for example, for controlling the operation of handpieces during ophthalmic surgery. Still more particularly, the present invention is directed to apparatus for the control of irrigation, aspiration in connection with phacoemulsification of natural lenses.
Ophthalmic surgical apparatus such as phacoemulsification apparatus, hereinabove noted, typically includes operating controls for regulating parameters, or functions, of the apparatus. The apparatus generally includes a handpiece for ultrasonic emulsifying a natural lens while irrigating the eye and aspirating particles of emulsified lens.
Various modalities of operation may be utilized in phacoemulsification apparatus which pertain to controlling various phases of the phacoemulsification procedure.
Typical apparatus includes a control cabinet, power supply, vacuum pump, as well as associated electronic hardware for operating multi-function handpiece in order to sonically emulsify eye tissue, irrigate the eye with saline solution, and aspirate the emulsified lens from the eye.
The control system typically utilizes a footpedal module which enables the operator to control many parameters associated with the operation. Such parameters include the aspiration rate, the intensity power applied to phaco handpiece as well as modes of operation of the handpiece itself. Thus, the use of the handpiece is facilitated by delegating these control functions to the footpedal device.
Heretofore, footpedals have been limited to detecting angular foot movement, i.e. depression of the footpedal and lateral foot movement, i.e. side switches on the footpedal. In this arrangement a pedal plate is connected to an encoder to provide control for a specified function This, of course, limits the number of variables controllable by the footpedal.
Because of the importance of the control features provided by footpedals, such devices must be user friendly in order to provide a surgeon the comfort and reliability expected in order not to initiate any disruption of the surgeon""s concentration when performing surgery.
For example additional switches are needed to effect xe2x80x9cfast accessxe2x80x9d changes desired by a surgeon so that more direct control of the surgical apparatus can be performed by a surgeon""s foot rather than by an assistant.
A computer for phacoemulsification may have three different settings. In each set, the flow rate, vacuum, and power level can be programmed. This is so called modern xe2x80x9cMultiple Modulation Phacoemulsificationxe2x80x9d MMP capability. The switches of footpedal can be programmed as the trigger to initiate these MMP. Normally, MMP1 (or phacol is set for moderate aspiration rate, moderate vacuum level. MMP2, is set to more efficiently remove cracked nucleus, and MMP3 generates the least amount of flow turbulence which is most suitable for sculpting the nucleus.
Footpedal switch can be used to enter various modes of operation. For example, an xe2x80x9cMMP UPxe2x80x9d mode can enable a surgeon to scroll from MMP1 to MMP2 to MMP3. An xe2x80x9cMMP Downxe2x80x9d mode can enable a surgeon to scroll from MMP3 to MMP2 to MMP1. Alternately, an xe2x80x9cMMP Rotatexe2x80x9d switch mode can provide requested xe2x80x9cKicksxe2x80x9d or xe2x80x9cconnectsxe2x80x9d in which the modes may rotate from MMP1-MMP2-MMP-3MMP1-MMPZ-etc.
As may be expected, different types of footpedals are preferred by various surgeons, with some surgeons preferring an accelerator type pedal in which the sole of the surgeon""s foot is utilized for depression, while others desire a pedal operable by the surgeon""s toe in order to depress the pedal.
In the past, this has led to the development of a multitude of footpedal devices of diverse configuration in order to provide the comfort and reliability desired by individual surgeons.
Unfortunately, when phacoemulsification apparatus is utilized by a number of physicians, a change in footpedals is often required, which is often inconvenient and may require recalibration of the apparatus. In addition, such alternative footpedals may not be available or offered by a manufacturer.
Accordingly, it is desirable to provide a footpedal which can be utilized by all attending physicians despite their preference for toe or sole activated pedals, while at the same time expanding the number of variables controllable by the footpedal. The present invention fulfills that need, while at the same time providing a footpedal which is comfortable to use in either a toe or sole depression configuration.
Apparatus in accordance with the present invention for controlling a handpiece during surgery generally includes a foot pedal which is pivotally mounted to a base for enabling depression thereof in order to provide control signals for handpiece operation. At least one support surface is disposed adjacent to the foot pedal on the base at a position enabling access thereto by a user""s foot and a first ribbon switch is disposed on the support surface. The first ribbon switch has a length sufficient to enable actuation thereof by the user""s foot without visual observation thereof by user. Importantly, the ribbon switch is actuable by depression thereof any point along the length of the switch. This feature facilities the use by a user without the visual observation of the switch.
A second support surface may be disposed adjacent to the foot pedal on the base at a position enabling access thereto by the user""s foot. A second ribbon switch is disposed on the second support surface and has a length sufficient to enable acuation thereof by the user""s foot without visual observation thereof by the user as similar to the first ribbon switch.
The surfaces may either be shrouds or fences disposed on either side of the foot pedal for enabling the ribbon switches to be disposed parallel to the foot pedal. The first and second ribbon switches enable the user to control at least two additional variables for controlling the handpiece.
In addition, a member may be provided which extends over the foot pedal in a generally transverse relationship therewith along with a third ribbon switch disposed on the member and having a length for enabling access thereto by a user""s foot without visual observation thereof by the user.
Still another embodiment of the present invention utilizes a forth ribbon switch disposed in and end-to-end relationship with the third ribbon switch on the member. Because of the transverse position of the member and third and forth ribbon switches over the foot pedal, a right and left hand orientation is provided for the user when the end-to-end relationship of the third and forth ribbon switches is centered approximately over the foot pedal.
When the foot pedal is positioned on the base to enable depression by a user toe or sole, the first and second ribbon switches are of sufficient length to enable access thereto by either the user""s toe or sole.
The present invention is also directed to an improvement to an existing foot pedal. In this embodiment, support surfaces are provided adjacent the existing foot pedal on a base at a position enabling access thereto by a user""s foot along with the first and second ribbon switches as hereinabove described.
In addition, a member extending over the existing foot pedal may be provided along with third and forth ribbon switches to enable the user to control additional variables to a surgical handpiece, otherwise not possible with the original foot pedal.